<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>do while 循环语句</title>

</head>
<body>
	<script>
		function star(row=5){
			star = 0
			do{
				let n =0 
				do{
				document.write('*')

				}while(++n <=star)
				document.write("<br/>")
			}while(++star <=row)
			
		}
		star(20)
	</script>
</body>
</html>